Feature/apdu null length returned (#285)

* Add APDU as NULL to get BACnet type lengths.

* Fix bacapp copy test to succeed

* fix BACnet REAL and DOUBLE decode

* Add unit test for NULL APDU encoding for length

* Add unit tests for bacapp context

* refactor host-n-port to hostnport.c module

* fix BVLC decoder

* additional unit testing for bacapp

* include bacdevobjpropref module in builds

* simplify bacapp snprintf to be able to return length

* adjust compiler for variable-length arrays

* fix bug found by scan-build

Authored-by: Steve Karg <skarg@users.sourceforge.net>

ports/pic18f6720/BACnet-Server.X/nbproject/configurations.xml

@@ -1,5 +1,5 @@
 <?xml version="1.0" encoding="UTF-8"?>
-<configurationDescriptor version="62">
+<configurationDescriptor version="65">
   <logicalFolder name="root" displayName="root" projectFiles="true">
     <logicalFolder name="HeaderFiles"
                    displayName="Header Files"
@@ -94,15 +94,25 @@
         <languageToolchainVersion>3.40</languageToolchainVersion>
         <platform>3</platform>
       </toolsSet>
+      <packs>
+        <pack name="PIC18Fxxxx_DFP" vendor="Microchip" version="1.2.26"/>
+      </packs>
+      <ScriptingSettings>
+      </ScriptingSettings>
       <compileType>
         <linkerTool>
           <linkerLibItems>
           </linkerLibItems>
         </linkerTool>
+        <archiverTool>
+        </archiverTool>
         <loading>
           <useAlternateLoadableFile>false</useAlternateLoadableFile>
+          <parseOnProdLoad>false</parseOnProdLoad>
           <alternateLoadableFile></alternateLoadableFile>
         </loading>
+        <subordinates>
+        </subordinates>
       </compileType>
       <makeCustomizationType>
         <makeCustomizationPreStepEnabled>false</makeCustomizationPreStepEnabled>